In the field of data storage, the term “backup” refers to the process of storing and archiving information to allow its restoration if needed, such as after a data loss or hardware failure. In a simple example, two copies of a data file can be maintained on a single physical storage medium to allow the information to be restored if one of the copies becomes corrupted. More sophisticated examples store backup copies on different physical media which are sometimes in different geographic locations, and employ incremental backup strategies that store complete copies of data and information describing subsequent changes to portions of the complete data.
Backup copies are often stored on low-performance storage devices that have low data transfer rates. This can lead to lengthy restore times, which can lead to inconvenience for the persons who are unable to access the data being restored and for the persons overseeing the restoration process. Traditional methods to improve restore times include monolithic, consolidated storage arrays that are costly and add multiple layers of switching and cabling complexity to a data center.